Objective The biomechanical characteristics of three internal fixation modes for femoral subtrochanteric spiral fracture in osteoporotic patients were compared and analyzed by finite element technology, so as to provide the basis for the optimization of fixation methods for femoral subtrochanteric spiral fracture. MethodsTen female patients with osteoporosis and femoral subtrochanteric spiral fractures caused by trauma, aged 65-75 years old, with a height of 160-170 cm and a body weight mass of 60-70 kg, were selected as the study subjects. The femur was scanned by spiral CT and a three-dimensional model of the femur was established by digital technology. The computer aided design models of proximal intramedullary nail (PFN), proximal femoral locking plate (PFLP), and the combination of the two (PFLP+PFN) were constructed under the condition of subtrochanteric fracture. Then the same load of 500 N was applied to the femoral head, and the stress distribution of the internal fixators, the stress distribution of the femur, and the displacement of femur after fracture fixation were compared and analyzed under the three finite element internal fixation modes, so as to evaluate the fixation effect. ResultsIn the PFLP fixation mode, the stress of the plate was mainly concentrated in the main screw channel, the stresses of the different part of the plate were not equal, and gradually decreased from the head to the tail. In the PFN fixation mode, the stress was concentrated in the upper part of the lateral middle segment. In the PFLP+PFN fixation mode, the maximum stress appeared between the first and the second screws in the lower segment, and the maximum stress appeared in the lateral part of the middle segment of the PFN. The maximum stress of PFLP+PFN fixation mode was significantly higher than that of PFLP fixation mode, but significantly lower than that of PFN fixation mode (P<0.05). In PFLP and PFN fixation modes, the maximum stress of femur appeared in the medial and lateral cortical bone of the middle femur and the lower side of the lowest screw. In PFLP+PFN fixation mode, the stress of femur concentrated in the medial and lateral of the middle femur. There was no significant difference in the maximum stress of femur among the three finite element fixation modes (P>0.05). The maximum displacement occurred at the femoral head after three finite element fixation modes were used to fix subtrochanteric femoral fractures. The maximum displacement of femur in PFLP fixation mode was the largest, followed by PFN, and PFLP+PFN was the minimum, with significant differences (P<0.05). ConclusionUnder static loading conditions, the PFLP+PFN fixation mode produces the smallest maximum displacement when compared with the single PFN and PFLP fixation modes, but its maximum plate stress is greater than the single PFN and PFLP fixation mode, suggesting that the combination mode has higher stability, but the plate load is greater, and the possibility of fixation failure is higher.
Objective To study the effects of the human keratinocyte growth factor 2 (hKGF-2) on the survival and differentiation of human neural stem cells (hNSCs). Methods The hNSCs at 17 passages preserved in liquid nitrogen were resuscitated and cultured for 7 days with normal methods to form neural spheres. The specific Nestin antigen and differentiated cells antigen were identified using immunohistochemistry technology. Some concentrated hNSCs were incubated in 12-well culture plate with 1 mL basic medium [(DMEM/F12 + N2 (1 ∶ 100) + epidermal growth factor (EGF) (20 ng/mL)] and divided into 7 groups, 6 wells each group. hKGF-2 (0, 10, 30, 60, 90, and 120 ng/mL) and bFGF (10 ng/mL) were added in groups A (control), B, C, D, E, F, and G, respectively. The neurospheres and the cell number were recorded for analyzing growth and multiplication of neural spheres. Some concentrated hNSCs were incubated in 6-well culture plate (cover glass coated with polylysine) with 3 mL DMEM/F12 medium and divided into 4 groups, 6 wells each group. N2 (1 ∶ 100), N2 (1 ∶ 100) + hKGF-2 (90 ng/mL), FBS (1 ∶ 20), and FBS (1 ∶ 20) + hKGF-2 (90 ng/mL) were added in groups A1, B1, C1, and D1, respectively. Then, the growth and multiplication of neural spheres were observed during culture; the separated neural spheres was identified and analyzed with indirect immunofluorescence and flow cytometry. Results Reanimated hNSCs could form neural spheres containing a lot of Nestin antigen; differentiated cells by induction expressed the specific antigens of neurofilament 200 (NF- 200) and glial fibrillary acidic protein (GFAP). At 7 days after culture, enlarged neural spheres were observed in each group. The neurospheres and the cell number of hNSCs increased with increased concentration of hKGF-2, showing a gradually increasing tendency; they were significantly higher in groups E, F, and G than that in groups A, B, C, and D (P lt; 0.05); significant differences were found among groups B, C, and D (P lt; 0.05), but no significant difference between groups A and B, and among groups E, F, and G (P gt; 0.05). After induction in vitro, the cell growth showed a progressive increase, significant difference was found among groups (P lt; 0.05); the percentage of NF-200 positive cells in group B1 was significantly higher than that in the other 3 groups (P lt; 0.05); the percentage of GFAP positive cells in group B1 was significantly lower than that in the other 3 groups (P lt; 0.05), but no significant difference among groups A1, C1, and D1 (P gt; 0.05). At 14 days after culture, cell growth reached the peak, which were mainly astero-cells. Conclusion The hNSCs are pure after incubated to 17 passages in vitro. hKGF-2 can promote the clone and the growth of differentiated cells, and increase the proportion of neuron.
Objective To explore the effect of tri pterygium glycoside (TG) on the skeletal muscle atrophy and apoptosis after nerve allograft. Methods Twenty Wistar male rats were adopted as donors, weighing 200-250 g, and the sciatic nerves were harvested. Fifty SD male rats were adopted as recipients, weighing 200-250 g. Fifty SD rats were made the models of10 mm right sciatic nerve defect randomly divided into five groups (n=10): group A, group B, group C, group D and group E.groups A and B received fresh nerve allograft, groups C and D received sciatic nerve allograft pretreated with TG, and group E received autograft. The SD rats were given medicine for 5 weeks from the second day after the transplantation: groups A and E were given physiological sal ine, groups B and D TG 5 mg/ (kg·d), and group C TG 2.5 mg/ (kg·d). At 3 and 6 weeks, respectively, after nerve transplantation, general observation was performed; the structure of skeletal muscles was observed by HE staining; the diameter of skeletal muscles was analyzed with Image-Pro Plus v5.2; the ultrastructure of skeletal muscles was observed by TEM; the expressions of Bax and Bcl-2 were detected by immunohistochemical staining; and the apoptosis of skeletal muscles was detected by TUNEL. Results All rats survived to the end of the experiment. In general observation, the skeletal muscles of SD rates atrophied to different degrees 3 weeks after operation. The muscular atrophy in group A was more serious at 6 weeks, and that in the other groups improved. The wet weight, fiber diameter and expression of Bcl-2 in group A were significantly lower than those in groups B, C, D and E (P lt; 0.01)；those in groups B, C and D were lower than those in group E (P lt; 0.05); and there were no significant differences among groups B, C and D (P gt; 0.05). The apoptosis index and expression of Bax in group A were significantly higher than those in groups B, C, D and E (P lt; 0.01)；those in groups B, C and D were higher than in groupE (Plt; 0.05); and there were no significant differences among groups B, C and D (P gt; 0.05). Three weeks after nerve allograft, under the l ight microscope, the muscle fibers became thin; under the TEM, the sarcoplasmic reticulum was expanded. Six weeks after nerve allograft, under the l ight microscope, the gap of the muscle fibers in group A was found to broaden and connective tissue hyperplasia occurred obviously; under the TEM, sarcomere damage, serious silk dissolution and fragmentary Z l ines were seen in group A, but the myofibrils were arranged tidily in the other groups, and the l ight band, dark band and sarcomere were clear. Conclusion TG can decrease the skeletal muscle atrophy and apoptosis after nerve allograft. The donor’s nerve that is pretreated with TG can reduce the dosage of immunosuppressant for the recipient after allograft.
Objective To investigate the appropriate concentration of tripterygium wilfordii and immunological rejection of rats’ sciatic nerve allograft with the tripterygium wilfordii’s pretreatment so as to explore tripterygium wilfordii’ s suppression. Methods Sixty SD rats (male, weighing 270-290 g), as sciatic nerve allograft acceptor were randomized into5 groups (groups A, B, C, D and E, n=12). To repair the sciatic nerve defect of SD rats, the Wistar rats’ sciatic nerve allografts about 15 mm long were used with 24 hours’ soak of different concentrations of tripterygium wilfordii (group A: 200 mg/L, group B: 400 mg/L, group C: 800 mg/L). The control groups (group D: the fresh sciatic nerve allograft from donors; group E: the fresh sciatic nerve allograft from themselves) were establ ished. At different time points after operation, the morphological examinations (the observation of histology, l ight microscope, electron microscope), the detection of myelin basic protein’s (MBP) content and the analyses of CD4+ and CD8+ T cells on the allografts in the acute phase were performed Results There was no significant difference in morphology among groups A, B and C, the adhesions between allografts and connective tissue were milder than that of group D, and the allografts’ morphous and the inflammatory cell infiltration were better than that of group D. The degeneration of myel in sheath was observed at different levels and there was no significant difference between group B and group E (P gt; 0.05). There was a significant difference in immunological rejection between groups A, B, C and group D (P lt; 0.05). Conclusion Tripterygium wilfordii can effectively suppress the acute immunological rejection in the early stage after operation, and protect the myel in sheath to a certain extent.
Objective To explore the anatomic basis for theanterior approach screw fixation through the C2 vertebral body into the C1 lateral mass and toinvestigate its primary clinical application. Methods Twenty-one adult corpse specimens were anatomically measured. The minimum lateral angle α, the maximum lateral angle β, and the maximum posterior angle γ were calculated based on the data from the anatomic measurement. All the specimens were given an X-ray examination, the minimum lateral angle α, the maximum lateral angle β, and the maximum posterior angle γ were measured. The statistical analysis was made on the data obtained from the calculation in the specimens and the measurement in the X-ray films. The simulation of the approach was made onthe specimen. From October 2004 to July 2006, the simulated approach was used in 5 patients (3 males, 2 females; age, 30-55 years; illness course, 3 months-2 years) with the old atlanto-axial joint dislocation . The Frankel grading system revealed the spinal cord injury degree as follows: 1 patientwas in Grade B, 2 in Grade C, and 2 in Grade D. All the patients were treated with this surgical approach. The postoperative X-ray and CT examinations were performed. Results Angle α was 14.0±1.6°, β was 30.0±2.3°, γ was 29.0±2.9°. No significant difference existed between the angles calculated in the specimens and measured in the X-ray films (Pgt;0.05). The angles for the practical application during operation were as follows: α was 11.2±1.6°, β was 28.8±2.3°, and γ was 29.3±2.9°. The follow-up for an average of 14 months revealed that 1 patient recovered to Grade C, 1 to Grade D2, and 3 to Grade D3 in the spinal cord function according the modified Frankel grading system.Conclusion The anterior approach screw fixation through the C2 vertebral body into the C1 lateral massis feasible and safe in treatment of the old atlantoaxial joint dislocation ifthe screw insertion is exact in direction. This technique only makes the atlas temporarily stable, and so the posterior bone graft should be added into the atlantoaxial joint immediately in the one- or two-stage operation so as to achieve a long-lasting stability.
Objective To evaluate an effect of the vascularendothelial growth factor (VEGF) geneactivated matrix (GAM) on repair of the sciatic nerve defect in rats. Methods The peripheral nerve extracellular matrix（ECM） was harvested by the chemical extraction from 30 SD rats. The VEGF-GAM comprised of ECM and the plasmids encoding VEGF. Thirty adult Wistar rats were made as a model of the asciatic nerve defect and were randomly divided into the following 3 groups(n=10): Group A (VEGF-GAM conduits), Group B (ECM conduits),and Group C (autografts). At 12 weeks, the rats from each groupwere subjected to an inspection for the walking tract analysis and electrophysiological and histomorphological studies.Results The VEGF DNA could be retained in GAM, promoting the transgene expressing in the sciatic nerve, and more importantly, in the axotomized neurons in the spinal cord for 12 weeks. The motor neuron recovery rate in Group A (79.13％±2.53％) was similar to that in Group C (75.26％±4.48％, Pgt;0.05), but significantly better than that in Group B (56.09％±1.89％, Plt;0.01). The number of the regenerationaxons in the distal sciatic nerve in Group A (13 463±794/mm2) was significantly lower than that in Group C (16 809±680/mm2, Plt; 0.01), but significantly higher than that in Group B (10 260±1 117/mm2,Plt;0.01). The motor nerve conduction velocity in Group A (16.44±1.65 m/s) was significantly lowerthan that in Group C (23.79±2.75 m/s, Plt;0.01), but significantly higherthan that in Group B (12.8 ±1.42 m/s, Plt;0.01). The recovery rate of thegastrocnemius muscle wet weight in Group A (71.40％±3.05%) was significantlylower than that in Group C (87.00％±1.87％,Plt;0.01), but significantly higher than that in Group B (50.00％±4.90％, Plt;0.01). The sciatic nerve function index in Group A （39.37%±4.81%） was significantly lower 〖KG6〗than that in Group C (26.27%±2.71%, Plt;0.01), but significantly higher than that in Group B (4693％±296％, Plt;0.01). Conclusion The results indicate that VEGF-GAM as a bridge can promote the functional recovery of the defected sciatic nerve in rats, but the effect is not so good as that by autografts.
Objective To review the progress of surgical treatment for the thoracolumbar spinal tuberculosis. Methods The related literature of surgical treatment for the thoracolumbar spinal tuberculosis was reviewed and analyzed from the aspects such as surgical approach, fixed segments, fusion ranges, bone graft, and bone graft material research progress. Results Most scholars prefer anterior or combined posterior approach for surgical treatment of thoracic and lumbar tuberculosis because it possessed advantage of precise effectiveness. In recent years, a simple posterior surgery achieved satisfactory effectiveness. The fixation segments are mainly composed of short segments or intervertebral fixation. The interbody fusion is better for the bone graft fusion range and manner, and the bone graft materials is most satisfied with autologous iliac Cage or titanium Cage filled with autologous cancellous bone. Conclusion The perfect strategy for treating the thoracolumbar spinal tuberculosis has not yet been developed, and the personalized therapy for different patients warrants further study.
Objective To investigate the effectiveness of arthroscopic medial retinaculum plication (MRP) for acute patellar dislocation (APD) in adolescents. Methods Between March 2007 and June 2011, 24 adolescent patients suffering from APD were treated by arthroscopic MRP. There were 14 males and 10 females, aged 8-18 years (mean, 12.7 years). The location was the left knee in 16 cases and the right knee in 8 cases. Injury was caused by sports in 19 cases, by traffic accident in 4 cases, and by heavy bruising in 1 case. The duration from injury to operation was 3 to 21 days with an average of 7.8 days. The results of floating patella test and dislocation apprehension test were both positive. MRI examination showed the arthroedema in all cases; associated injuries included medial retinaculum injury in 20 cases, medial patellar injury in 8 cases, and meniscus tear in 5 cases. Results All incisions healed by first intention without complication of infection or neurovascular injury. All the patients were followed up 12-36 months (mean, 14.6 months). Only 2 patients suffered from patellar re-dislocation at 4 months and 6 months after operation respectively. The knee joint activity returned to normal at 12 months. The Lysholm, Kujala, and International Knee Documentation Committee (IKDC) scores at 3 and 12 months after operation were significantly higher than those before operation (P lt; 0.05), and the scores at 12 months were significantly higher than those at 3 months (P lt; 0.05). Conclusion Treatment of APD with arthroscopic MRP has the advantages of minor trauma and good knee functional improvement. The technique can decrease incidence of patellar re-dislocation in adolescent.
Objective To investigate the injury mechanism, clinical characteristics, and treatments of Segond fracture and complications. Methods Fifteen patients suffering from Segond fracture were treated between January 2007 and December 2011. There were 10 males and 5 females, aged 16-50 years (mean, 31.8 years). Fracture was caused by traffic accident in 8 cases, by sports in 6 cases, and by bruise in 1 case. Before operation, the knee range of motion (ROM) was (36.60 ± 8.94)°; the Lysholm score was 32.27 ± 3.73; and the International Knee Documentation Committee (IKDC) score was 42.34 ± 4.97. The duration from injury to operation was 1-3 weeks with an average of 1.2 weeks. In 12 patients having associated anterior cruciate ligament (ACL) injury, arthroscopic reconstruction of ACL was performed with allogeneic anterior tibial tendon; in 2 patients having associated avulsion fracture of the intercondylar eminence of the tibia, arthroscopic fracture reduction and fixation with Orthocord wire were performed. In 8 patients having associated meniscus injury, meniscus suture and meniscectomy were performed in 3 and 5 patients, respectively. In 7 patients having associated collateral ligament injury, conservative treatment was given in 5 patients, and medial collateral ligament was repair in 2 patients. Results All incisions healed primarily without complications of infection and nerve or blood vessel injury. All the patient were followed up 12-16 months (mean, 14.3 months). At 12 months after operation, the results of anterior drawer test, Lachman test, and lateral stress test were all negative. The knee ROM was (129.27 ± 5.89)°, the IKDC score and Lysholm score were significantly increased to 89.45 ± 3.05 and 87.87 ± 4.12 at 12 months after operation; all showing significant differences when compared with preoperative values (P lt; 0.05). Conclusion Segond fracture is often combined with ACL, collateral ligament, and meniscus injuries, and the evidence of Segond fracture can bly suggests the knee injury. Personalized treatment should be chosen according to complications.
Objective To explore the method and outcome of knee resurfacing arthroplasty in treating late-staged diffuse pigmented villonodular synovitis (PVNS). Methods Between November 2002 and May 2009, 11 cases of late-staged diffuse PVNS were treated, including 3 males and 8 females with an average age of 51.2 years (range, 42-63 years). The diseaseduration was 2.5-10.0 years (mean, 5.2 years). Unilateral knee was involved in all patients, including 7 left knees and 4 right knees. Nine patients had a history of trauma and 2 cases had no obvious inducing factors. The range of motion was (90.1 ± 17.2)° and Hospital for Special Surgery Knee Score (HSS) was 68.9 ± 8.7. After synovectomy, knee resurfacing arthroplasty was performed in all patients. Results Superficial infection of the incision occurred in 1 case at 6 days postoperatively and was cured after debridement; other incisions healed by first intention. Limited flexion and extension, incomplete palsy of common peroneal nerve, and deep venous thrombosis occurred in 1 case respectively, and were cured or improved after symptomatic treatment. All the 11 cases were followed up 38 months on median (range, 13 to 102 months). Two cases developed chronic pain and were not given treatment. Recurrence occurred in 1 case 12 months postoperatively and recovered after synovectomy again. X-ray films showed no signs of loosening, sinking, and bone destruction. At last follow-up, the range of motion was (109.1 ± 18.6)° and HSS score was 86.7 ± 9.3, showing significant differences when compared with those before operation (P lt; 0.05). According to the HSS score system, the results were excellent in 6 cases, good in 3, fair in 1, bad in 1, and the excellent and good rate was 81.8%. Conclusion A combination of knee resurfacing arthroplasty and synovectomy for the treatment of late-staged diffuse PVNS is able to get a good cl inical results in restoration of function, improvememt of the l ife quality, and decrease of recurrence rate.